CurriculumGrade 9Science

The Carbon Cycle

Aligned to HS-LS2-5 — Next Generation Science Standards.

What this lesson teaches

Carbon moves among living things, the air, water, and rock. Photosynthesis and respiration swap it with the atmosphere, oceans dissolve it, and rocks store it for long ages.

Worked example

Carbon in atmospheric carbon dioxide dissolves into the ocean, is built into a shell by a clam, and after the clam dies becomes limestone rock stored for millions of years.

Practice questions

  1. List the four reservoirs where carbon is stored.
  2. Diagram a path for one carbon atom to move from the air into a rock.
  3. Explain how burning fossil fuels shifts carbon between reservoirs faster than natural processes.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

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En español

El ciclo del carbono

El carbono se mueve entre los seres vivos, el aire, el agua y las rocas. La fotosíntesis y la respiración lo intercambian con la atmósfera, los océanos lo disuelven y las rocas lo almacenan durante largas eras.

Ejemplo: El carbono del dióxido de carbono atmosférico se disuelve en el océano, una almeja lo incorpora a su concha y, cuando la almeja muere, se convierte en roca caliza almacenada durante millones de años.

More HS-LS2 Ecosystems lessons

Populations and BiodiversityHS-LS2-2Matter and Energy in EcosystemsHS-LS2-3Energy PyramidsHS-LS2-4Ecosystem StabilityHS-LS2-6Protecting BiodiversityHS-LS2-7Group Behavior and SurvivalHS-LS2-8

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